First FF body - Used 6d mk1 or 5d mk3?

I'm looking to purchase my first FF body and i thought i should look for a used one for budget reasons. I've found two for sale, but i'm not really sure which to pick. The first one is a 5D mk3 with about 100k actuations at about 1160 dollars. The guy who sells it have great recommendations, is a freelance photographer and the camera seems to be in great condition. The only problem is that i live about 2 hours away from this guy, so i need to trust him to not scam me. The second one is a 6D mk1 with about 30k actuations for 870 dollars sold by a photo store with a 3 months warranty. The body seems to be in good condition with a few scratches.

I'm really leaning towards the 5D mk3, but i would like your opinion on what to do. The shortcomings of the 6D don't scare me that much as i have 7D in great condition to fill the gap.